Why is Penny naked?

Sheldon reveals something to the Gang

In The Cooper-Hofstadter apartment

Leonerd Hofstadter finally got tired of his realtionship with Penny Teller. "Leonerd, Why are complainting that Sheldon trying to be your firend" said Penny, "Hes an big Baby" said Leonerd, Sheldon hissed "Thats it I think i shouldnt say this at least I've an an Backbone, you like to get push around since your an Invertebrate, Raj cant talk to women since he has no self steam, Wolowitz cant do anything since hes walking time bomb no Offense, You have no backbone, if you want to know my childhood, you just ask Leonerd, you cant be an big boy when it comes to something I am your firend also Raj and Howards despite we have Different minds, Hell Lets start with something that why i am Insecure I was married before until my smart hot wife got into an coma was so upset I told my family to put my son up for Adoption so I can feel no connections to my wife who still havent woken up from" screamed Sheldon, Raj and Howard went to Comfort Sheldon, "Also Theres times I would want to have Penny cheat on you with me since you dont really love her and I love her so much I want her to stripped down naked and have coitus with her until She's pregrant with my son's little sibling". Sheldon leaves the apartment Howard and Raj know its Comic Book day so they follow Sheldon out. Penny smiled " I think i would be an better Mrs Cooper than Mrs Hofstadter anyways". Penny left the apartment to go be with Sheldon, Raj and Howard.